You won’t be able to do this directly in OptiMiser. We do have controls to model ceiling fans. The are in the frame on the bottom of the Cooling tab labeled Fans. However, the fans are modeled per the RESNET standard to run at medium speed for 10.5 hours per day and only during cooling months where the average temperature is greater than 63F. If the fans are indeed running year round, then you could multiply the number of fans by the ratios 24h/10.5h and 12/CoolingMonths. Any change you make to the ceiling fans will be linked to the Cooling improvement, so you will have to check that row in the Details table to see the impact.
However, there are a couple of problems you should consider
- Turning off all of the fans is likely to alter the occupant behavior with the thermostat. They are likely very used to constantly circulating air and the temperature that they need to be comfortable may be different without it.
- Depending on the effectiveness of the HVAC distribution system, turning off all the ceiling fans could also have a significant impact on the temperature distribution in the home.
Neither of these impacts can be modeled.